# -*- coding: utf-8 -*-

# Copyright © Cloud Linux GmbH & Cloud Linux Software, Inc 2010-2021 All Rights Reserved
#
# Licensed under CLOUD LINUX LICENSE AGREEMENT
# http://cloudlinux.com/docs/LICENSE.TXT

"""
This module contains validation schema for config file loaded values
"""

import re

from schema import Schema, And, Optional, Use, SchemaError

from ..internal.exceptions import SSAError

_MAX_IGNORE_LIST_LENGTH = 10000
_MAX_IGNORE_PATTERNS = 100
# URLs in ssa.db can contain UTF-8 (the agent regex only blocks control chars
# and a few HTTP metacharacters), and fnmatch handles UTF-8 fine, so the
# validator only rejects the concrete risk: control characters in patterns.
_DISALLOWED_CHARS_RE = re.compile(r'[\x00-\x1f\x7f]')
_WILDCARD_ONLY_CHARS = {'*', '?'}


def _validate_ignore_list(s):
    s = str(s)
    if len(s) > _MAX_IGNORE_LIST_LENGTH:
        raise SchemaError(
            f'ignore_list exceeds maximum length of {_MAX_IGNORE_LIST_LENGTH}')
    patterns = [p.strip() for p in s.split(',') if p.strip()]
    if len(patterns) > _MAX_IGNORE_PATTERNS:
        raise SchemaError(
            f'ignore_list exceeds maximum of {_MAX_IGNORE_PATTERNS} patterns')
    for p in patterns:
        # Reject any pattern composed solely of fnmatch wildcards
        # (*, **, ?*, *?*, ?, ??, ...) — they all match everything or any
        # fixed-length string and would silence the entire report.
        if set(p) <= _WILDCARD_ONLY_CHARS:
            raise SchemaError(
                f'ignore_list pattern must not be wildcards-only: {p!r}')
        if _DISALLOWED_CHARS_RE.search(p):
            raise SchemaError(
                f'ignore_list pattern contains control characters: {p!r}')
    return s


configuration_schema = Schema({
    Optional('domains_number'): And(int, lambda n: n >= 0,
                                    error='number of domains should be a positive integer'),
    Optional('urls_number'): And(int, lambda n: n > 0,
                                 error='number of URLs should be a positive integer'),
    Optional('requests_duration'): And(Use(lambda n: float(n)),
                                       lambda n: n > 0.0,
                                       error='request duration should be positive'),
    Optional('request_number'): And(int, lambda n: n > 0,
                                    error='number of requests should be a positive integer'),
    Optional('time'): And(int, lambda n: 0 <= n <= 12,
                          error='time should be a positive integer between 1 and 12, or 0'),
    Optional('correlation'): And(bool,
                                 error='bad correlation value, should be On or Off'),
    Optional('correlation_coefficient'): And(Use(lambda n: float(n)),
                                             lambda n: 0.0 < n <= 1.0,
                                             error='correlation coefficient could not be negative or greater than 1'),
    Optional('ignore_list'): Use(_validate_ignore_list),
    Optional('summary_notification_enabled'): And(bool,
                                                  error='bad notification value, should be On or Off'),
})


def validate(data: dict, scheme: Schema = configuration_schema) -> dict:
    """
    Validate given data.
    Returns validated data
    """
    try:
        return scheme.validate(data)
    except SchemaError as e:
        raise SSAError(f'Invalid configuration: {str(e)}')